11-27-2008 09:29 PM #1
468 Big Block Noise
Help me out please?
I had a machine shop rebuild a 454, (1970 car motor) I’m not trying to beat the builder up, however I don’t like a noise, I am hearing in the engine bay. It sounds like a power steering pump knock. I have laid out $5500.00 on the motor. I have had the car back to the machine shop over this noise. The engine builder told me to drive it; he did not think it would hurt.
My concern is, it was two years ago when he rebuilt the motor, he was told upon dropping the motor off, it would be a couple of years before the motor would be fired and was suppose to take specials provisions for that, and now firing it the first time six month ago. Bet you already know what he said “Drive it”.
Let me tell you what I know about the engine. I don’t have all of the specs with me right now, what I can tell you. The motor is a 454 was bored .60 over. Dome Pistons, I have been running 100 percent Cam II.
It was full long blocks rebuild; the cam was larger than a stock 427. it was the largest, I could go with, with out going to a solid lift cam (I wanted to build a prostreet car I could drive not continue to have to adjust lifters on, (old school I guess). Dummy)
I am running a 4500 Stall Convertor I did remove the convertor bolts to make sure their was nothing behind the transmission that may have been causing this fuss.
Than I thought maybe, it was a detonation problem, so I tried a 50/50 mix to no evail.
This noise does not change with engine Rpms.
I did drop the Belts to make sure the power steering / water pump was not the corporate (Nope) not it.
I have had the cam cover off to make sure the cam was not walking. And thought about the risk pins but the noise does not change with the rpm, and it does have an electric fuel pump on it.
So while it is down in the back it’s not two late to tear it back apart up front. Let me know what you think.
I have had it on the strip on one occasion where it turned numbers in the Low and 8s, in the 1/8 mile with 2:73 Gears.
I now have the rear end out laying in a set of 4:88s to get the car in the torque range the motor is looking for. However before I put it in the higher rpms on the strip this noise now concerns me.
This is the first time I have ever used this forrum so you may have to walk me through!
Thanks for all your help!!!!
Last edited by ProStreetMonte; 11-27-2008 at 09:32 PM.
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the pistons are hitting the heads ? valve hitting the pistons ?? you did not say what heads you have but if o ports with a closed chamber pistons like a old trw then they will hit on the EX side of the dome or a je/srp or others big dome with the older iron open chamber heads they can hit to. as for solid cams on the street i have used solid rollers and flat lifter cams for over 20 years . you do not have to just them all the time two times a year or less i check them .the only time things change is if you wipe a cam or bend some parts or valve train is wearing out
Last edited by pat mccarthy; 11-27-2008 at 11:14 PM.
Being two years ago probly no warrnty left if you got one,so pull the heads and see if you have a clerance issue,I had one that sounded like colapsed lifters ticking just went with .040compressed thicker head gasket.thats if valve is hitting piston ,not piston hitting head like Pat said.you'v made some runs on it so you will see what's hitting for sure.if that checks out could it be a froze up rist pin from setting Pat?.
i would think it could be many things hard to say could be a wrist pin bushing or piston slap i would not say oh hell it is fine drive it ??as for a warranty good luck on that i back my machine work and assembly. i am not say that this is what happen here .some guys think it the engine builder that should give them a safty net to do dumb things and back up there butt
Thanks, Sorry guys they are the open chamber heads, wow never thought of it that way. but it does sound like a piston coming up and hitting the bottom of the head. I will update you on what I find when I tear it down.
Now, you have me going, what is involve with converting this cam and lifter to a roller retro. I would like to hear the motor shake a little bit harder. in doing this, should I find that the piston is hitting the head, are what are we talking about doing to raise the head up? I dont feel that it is the piston hitting the valve only because I think more problems would have already developed. such as bent valves when adjusting them. Let me know what your thoughts are.
I will keep you up to date when I remove the heads......
you do not raise the head you cut the dome on the piston or open up the head chamber if the valve hit they get bent and would run very bad retro roller cam hyd need retro push rods and retro lifters thust button you may need better valve springs if you use a iron core cam you will not need to do any thing with the dist gear or fuel pump push rod if your using a mech pump i done many hyd rollers retrosOriginally Posted by ProStreetMonte
Sorry to here about your build problem:
I had some of the same problems myself, about (3) years ago, I had my engine built by a machinist I thought new what they were doing. It was a big block ford with 13.1 compression and flat tapper cam, built to perform over 600 hp. Well after the start up and took it to a recommended mechanic with a dyno to tune it. He found right off that the cam had some lopes that were wore down, and he was sure that metal was being circulating around in the engine. Well he was so right.
Upset, yea, spent a lot of money yea, over 6 thousand. So I took the engine out and took the short block back to them. They broke it down wash it, clean it put new bearings, ect. ect.
Took it back to a real engine builder. and he broke it down again, found some other problems and rebuilt it with a roller cam and some other goodies. Another 4500.00.
A, I could have went off, and probably found myself in jail.
But I have more to lose than to gain, by that behavior. Life is to short to lose it over some jerks.
67 cougar burn rubber not your soul!
I would agree with others. Get the casting # off the heads and look up the chamber size to identify them first. Then pull the heads and inspect. If all appears well I would clay a piston and turn it over by hand and look to the clay for clearance issues. If there is evidence of a problem Id take heads to shop to disassemble heads and inspect all vavle to see if bent which often they will just a little and not noticed until removed from heads. Have vavle job done and replace necessary vavles. If clearance is an issue typically you can as Pat stated have pistons cut to accomodate is the cheapest way I know of. While its apart you can check out cam. Id be a little worried if it was me that a flat tapped cam sitting assembled for 2 years and not fired up that most all the cam lube break in fell off the cam and it is wiped as well.
Just suggestions to look at.
I have cruised thru this thread a couple times previously and what no one has responded to was that you state that the noise doesn't change with RPM----so it probably isn't an engine noise
Futher you state thate it has an electric fuel pump---what kind???? simply disconnect the pump to see if the noise stops